Wayne Junction Substation Reconstruction

Project Description

SEPTA required detailed engineering base mapping along the Wayne Interlocking rail corridor to support design for rebuilding the Wayne Junction Substation. The project area covered approximately 0.5 miles of the active Chestnut Hill/Fox Chase Line, including four main tracks between Liberty Yard and Roberts Yard.

Gannett Fleming retained TULLOCH to complete the corridor survey under tight operational constraints. Data acquisition took place overnight during a limited SEPTA track-access window, allowing the team to capture detailed existing conditions while minimizing disruption to rail operations.

TULLOCH combined high-density mobile LiDAR with surveyed control to create a precise digital representation of the corridor. The resulting point cloud and extracted features were used to develop a surface model and fully drafted 3D engineering base plan in accordance with SEPTA CAD standards.

Scope of Services

Establishment of two primary project control points tied to high-order NGS monuments through static GNSS surveying
RTK GNSS survey of registration points positioned at approximately 500-foot intervals
Mobile LiDAR acquisition along approximately 0.5 miles of active SEPTA regional rail corridor
High-density point cloud collection averaging approximately 3,000 points per square metre on hard surfaces
Absolute hard-surface accuracy of less than 0.05 ft RMSE
LiDAR validation and control using surveyed registration points
Topographic feature extraction and mapping to SEPTA CAD standards and specifications
Automated, semi-manual, and top-down digitizing of rail corridor features
Surface model development
Fully drafted 3D AutoCAD Civil 3D engineering base plan